JPH1167142A - Ion implanter - Google Patents

Abstract

PROBLEM TO BE SOLVED: To control an angle of a wafer holder according to how an ion beam is implanted. SOLUTION: Plural wafer holders 26 are placed freely rotatably on a rotating disk 20, a bottom side of each wafer holder 26 is connected to a counter weight 36 via a rod 34, and the rod 34 is supported freely rotatably by a gate type shaft 40. Before an ion beam 46 is implanted, the wafer holder 26 is held almost parallel with a horizontal plane by the weight of the counter weight 36, and when a centrifugal force is applied to the wafer holder 26 as the disk 20 rotates, the wafer holder 26 is held so that a wafer 32 on the wafer holder 26 is inclined at an angle of inclination θ, in order to implant the ion beam 46 to the inclined wafer 32.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ion implantation apparatus, and more particularly to a SIMOX (Separation by Immo) suitable for implanting oxygen ions into a silicon wafer.
planted Oxygen).

[0002]

2. Description of the Related Art Conventionally, when a semiconductor layer is formed on a silicon substrate via an insulating layer, SOI (Silicon) is formed by a bonding method or a SIMOX method.
It is known to form OnInsulators. In the bonding method, an insulating film is inserted between two silicon wafers, the respective silicon wafers are bonded to each other via the insulating film, and then one silicon wafer is polished to a specified thickness. I have. On the other hand, in the SIMOX method, oxygen ions are implanted into a silicon wafer (silicon substrate), and then the silicon wafer is placed in a high-temperature furnace and heated (annealing treatment) to form an insulating layer (SiO ₂ ) in the silicon wafer. And forming a SOI by separating the silicon wafer into two layers based on the insulating layer. According to this method, the step of polishing the silicon wafer, unlike the bonding method, becomes unnecessary. For example, Japanese Patent Application Laid-Open No. 1-189845 and Japanese Patent Application Laid-Open No.
Japanese Patent Application Laid-Open Nos. 159,538 and 62-47940 have been proposed.

[0003]

SUMMARY OF THE INVENTION Among ion implanters, especially in a SIMOX ion implanter, the SI
From the application of MOX, uniformity of oxygen ion implantation distribution and minimization of particles (dust) and metal contamination are important issues in the process. Ie SIMO
For X wafers, as oxygen ions, 10 17 to 10 1
Eight implantations / cm ² are required, and the angle of incidence of the ion beam on the wafer is an important factor among the implantation conditions. However, in the related art, sufficient consideration has not been given to controlling the angle of the wafer in accordance with the ion beam implantation condition (implantation condition). That is,
When mounting the wafer on the wafer holder, it is necessary to mount the wafer on the wafer holder with the wafer facing upward. When implanting (irradiating) the ion beam onto the wafer mounted on the wafer holder, the wafer is inclined with respect to the horizontal plane. Otherwise, particles and the like will adhere to the wafer and will be affected by particles and metal contamination. For this reason, in the ion implantation apparatus for SIMOX, it is necessary to mount the wafer on the wafer holder with the wafer facing upward when mounting the wafer on the wafer holder. It is necessary to keep it at an inclined angle.

An object of the present invention is to provide an ion implantation apparatus capable of controlling the angle of a wafer according to the ion beam implantation situation.

[0005]

SUMMARY OF THE INVENTION In order to achieve the above object, the present invention provides a rotating disk disposed in a processing chamber and rotatably supported on a rotating shaft intersecting with a horizontal plane, and rotating the rotating disk. Rotating drive means, a plurality of wafer holders arranged above the rotating disk and distributed along the circumferential direction thereof so that wafers can be placed thereon, and each wafer holder fixed on the rotating disk so as to be rotatable. An ion implantation apparatus comprises: a plurality of wafer holder supporting means for supporting; and an ion beam irradiating means disposed outside the processing chamber and irradiating an ion beam from an ion source toward a wafer on the wafer holder.

In configuring the ion implantation apparatus, a rotating disk that is disposed in a processing chamber and is rotatably supported by a rotating shaft that intersects an inclined surface that is inclined from a horizontal plane can be used.

Further, the following elements can be added when configuring each of the ion implantation apparatuses.

(1) The plurality of wafer holder supporting means supports each wafer holder parallel to the horizontal plane when the ion beam implantation is stopped, and at an angle inclined with respect to the horizontal plane according to the centrifugal force acting on each wafer holder when the rotating disk rotates. Support each wafer holder.

(2) The plurality of wafer holder supporting means supports each wafer holder parallel to the horizontal plane when the ion beam implantation is stopped, and at an angle inclined with respect to the horizontal plane according to the number of rotations of the rotating disk when the rotating disk rotates. And a driving mechanism for driving each wafer holder.

(3) Reciprocating drive means for reciprocating the rotating disk along its radial direction is provided.

(4) The ion beam irradiation means has a scanning means for scanning the ion beam from the ion source on the wafer on the wafer holder in a vertical or horizontal direction.

Further, according to the present invention, a plurality of wafer holders are dispersedly arranged along a circumferential direction above a rotating disk which is disposed in a processing chamber and is rotatably supported by a rotating shaft intersecting a horizontal plane. When the ion beam implantation is stopped, each wafer holder on which a wafer is mounted is rotatably supported in an upward state, and when the rotating disk is rotated, each wafer holder is inclined with respect to a horizontal plane according to the centrifugal force acting on each wafer holder. An ion implantation apparatus is configured by irradiating an ion beam from an ion source to a wafer on a supported and inclined wafer holder.

When the ion implantation apparatus is constructed, a rotating disk that is disposed in a processing chamber and rotatably supported by a rotating shaft that intersects an inclined surface inclined in a horizontal plane can be used.

According to the above means, when the ion beam implantation is stopped, each wafer holder on the rotating disk is supported in parallel with the horizontal plane, so that the wafer can be mounted on each wafer holder in an upward state. On the other hand, when the rotating disk rotates, each wafer holder can be held at an angle inclined with respect to the horizontal plane by the centrifugal force acting on each wafer holder or the driving of the drive mechanism, so that the wafer held in a state inclined with respect to the horizontal plane It is possible to irradiate (implant) the ion beam with respect to this, and it is possible to prevent particles and metal particles from adhering to the wafer when the ion beam is implanted into the wafer.

[0015]

DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 shows a SIMO according to an embodiment of the present invention.
1 is an overall configuration diagram of an ion implantation apparatus for X. FIG. In FIG. 1, a processing room (end station) 1 is provided on a floor 10.
2 is installed, and an ion source 1 is provided near the processing chamber 12.
4. The mass separator 16 and the 30-degree deflector 18 are arranged. A disk-shaped rotary disk 20 is rotatably disposed in the processing chamber 12, and the rotary disk 20 is rotatably supported by a rotary shaft 22 orthogonal to a horizontal plane.
The rotation shaft 22 is connected to a drive shaft of a motor 24 as a rotation drive unit. The rotation of the motor 24 causes the rotation disk 20 to rotate about the rotation shaft 22. Above the rotating disk 20, a plurality of wafer holders 26 are dispersedly arranged along the circumferential direction of the rotating disk 20. Each wafer holder 26 has a disk-shaped main body 28, and an annular projection 3
0 is formed. Then, a wafer (silicon wafer) 32 is placed in a region surrounded by the projection 30. When the implantation of the ion beam into the wafer 32 is stopped or when the rotating disk 20 is stopped, each wafer holder 26 is held substantially parallel to the horizontal plane, and the centrifugal force acting on the wafer holder 26 when the rotating disk 20 rotates. Each wafer holder 26 is provided with wafer holder support means in order to hold the wafer holder 26 in a state inclined with respect to the horizontal plane.

That is, as shown in FIG. 2, a cylindrical rod 34 is fixed to the bottom side of the main body 28 of each wafer holder 26, and a counterweight 36 is connected to the tip side of the rod 34. The center of the rod 34 is rotatably supported by a portal shaft 40 via a rotary bearing 38. The portal shaft 40 is fixed to the upper surface of the rotating disk 20 via a base 44 by bolts 42. The weight of the counterweight 36 is such that the wafer 32 on the wafer holder 26 faces upward when the rotation of the rotary disk 20 is stopped, and when the rotation of the rotary disk 20 is stopped.
As shown in FIGS. 3 and 4, the wafer holder 26 is set to be inclined with respect to the horizontal plane according to the centrifugal force acting on the wafer holder 26.

That is, the counterweight 36 is heavier than the wafer holder 26, and when the rotation of the rotary disk 20 is stopped, the counterweight 36 supports the wafer holder 26 rotatably supported by the portal shaft 40 in an upward state. . On the other hand, when the rotating disk is rotated, the shaft 4 is rotated by the centrifugal force acting on the wafer holder 26 and the counterweight 36 as the rotating disk 20 rotates.
The difference between the weight on the side of the wafer holder 26 centered on 0 and the weight on the side of the counterweight 36 causes the wafer holder 26 to be inclined by an inclination angle γ with respect to the horizontal plane.
That is, the rotation of the rotating disk 20 (the number of rotations)
It is designed to stand according to. This is due to the centrifugal force F, which is represented by the following equation.

F = mrω ² m: mass r: radius of rotation ω: number of rotations of rotating disk 20 The tilt angle γ of the wafer 32 can be controlled by the mass of the counterweight 36 and the number of rotations of the rotating disk 20.
This means that the beam incident angle θ on the wafer 32 can be controlled. In addition, as the inclination angle γ of the wafer 32 increases, the component of the centrifugal force of the wafer 32 itself pushing in the direction perpendicular to the wafer holder 26 also increases, thereby preventing the charge-up due to an increase in the wafer holding force and a decrease in the contact resistance. can do.

The ion beam 46 irradiated (implanted) on the wafer 32 is outputted from the 30-degree deflector 18. The ion beam 46 is separated from the ion beam emitted from the ion source 14 by the mass separator 16 so as to have a predetermined mass, for example, by separating only oxygen ions. It is generated with the ions removed.

When the ion beam 46 of oxygen ions is implanted into the wafer 32 by using the ion implantation apparatus having the above-described structure, the ion beam from the ion source 14 is implanted into the wafer 32 before the ion beam 46 is implanted into the wafer 32. The wafer 32 is loaded into the processing chamber 12 from the side, and the wafer 32 is sequentially mounted on the wafer holder 26 facing upward. After the wafers 32 are mounted on all the wafer holders 26, the motor 24 is driven to gradually increase the rotation speed of the motor 24.
The centrifugal force associated with the rotation of the rotating disk 20 causes the wafer holder 2
6. Acts on the counterweight 36, and when the wafer 32 reaches the inclination angle γ, the ion beam 46 emitted from the 30-degree deflector 18 is injected toward the wafer 32. At this time, when the entire rotary disk 20 is reciprocated by using a reciprocating drive means (not shown) for reciprocating the rotary disk 20 in a direction perpendicular to the paper surface, the ion beam 46 can be implanted over the entire surface of the wafer 32. . After uniformly implanting the ion beam 46 into all the wafers 32, the rotation speed of the motor 24 is gradually reduced to stop the rotation of the rotary disk 20. When the rotating disk 20 is stopped, the wafer 32 is taken out of the wafer holder 26 when the wafer holder 26 faces upward.

According to the present embodiment, before ion beam implantation, the wafer 32 is held in an upward state substantially parallel to the horizontal plane, and during ion beam implantation, the wafer 32 is held in a state inclined by the inclination angle γ. Therefore, the wafer holder 26 and the wafer 3
2 can be controlled, and the influence of particles and metal contamination can be suppressed.

In this embodiment, since it is not necessary to tilt the rotary disk 20 itself, the wafer 32
The height of the processing chamber 12 can also be reduced when tilting.

In the above embodiment, the wafer holder 2
The use of a centrifugal force when tilting 6 has been described. However, a configuration in which a drive mechanism that drives wafer holder 26 to a position inclined at an angle to the horizontal plane in accordance with the number of rotations of rotating disk 20 is connected to wafer holder 26. Can also be adopted.

In the above embodiment, the wafer 32
Although the reciprocating drive means is used to implant the ion beam 46 over the entire surface of the wafer 32, the ion beam from the ion source 14 is supplied to the wafer 32 by the ion beam irradiation means including the mass separator 16 and the 30-degree deflector 18.
May be provided with a function as a scanning unit that scans vertically or horizontally.

FIG. 5 shows another embodiment of the present invention.

In the present embodiment, the rotating disk 20 is rotatably supported by the rotating shaft 22 that intersects an inclined surface that is inclined from the horizontal plane, and the 30-degree deflector 18 emits an ion beam 46 parallel to the horizontal plane. Further processing chamber 12
The loading and unloading of the wafer 32 is carried out from the side surface of the device, and the other configuration is the same as that of the above embodiment.

According to the present embodiment, the same effects as those of the above embodiment can be obtained, and the rotating disk 20 is disposed in a state inclined in advance with respect to the horizontal plane. When the rotation speed is low, the inclination angle of the wafer 32 can be set to γ.

Further, in the present embodiment, since the rotating disk 20 is fixed in advance in a state inclined with respect to the horizontal plane, the ion beam 46 parallel to the horizontal plane can be injected into the wafer 32.

[0030]

As described above, according to the present invention,
Since the angle of the wafer holder is controlled in accordance with the ion beam implantation state, it is possible to suppress the influence of particles and metal contamination when implanting the ion beam into the wafer.

[Brief description of the drawings]

FIG. 1 is an overall configuration diagram of an ion implantation apparatus according to a first embodiment of the present invention.

FIG. 2 is a view for explaining a configuration of a wafer holder supporting means before ion beam implantation.

FIG. 3 is a view for explaining a configuration of a wafer holder supporting means at the time of ion beam implantation.

FIG. 4 is a diagram for explaining an operation when implanting an ion beam into a wafer.

FIG. 5 is a side view of a main part showing a second embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 12 Processing chamber 14 Ion source 16 Mass separator 18 30 degree deflector 20 Rotating disk 22 Rotating axis 24 Motor 26 Wafer holder 32 Wafer 36 Counter weight 38 Rotating bearing 40 Portal shaft 46 Ion beam

Claims (8)

[Claims] A rotary disk disposed in a processing chamber and rotatably supported by a rotary shaft intersecting a horizontal plane; a rotary driving means for rotating the rotary disk; and a rotary drive above the rotary disk along a circumferential direction thereof. A plurality of wafer holders arranged so as to be able to place wafers in a distributed manner, a plurality of wafer holder supporting means fixed on a rotating disk and rotatably supporting each wafer holder, and an ion arranged outside the processing chamber. An ion beam irradiation means for irradiating an ion beam from a source toward a wafer on a wafer holder. 2. A rotating disk disposed in a processing chamber and rotatably supported by a rotating shaft intersecting an inclined surface inclined from a horizontal plane, a rotating drive means for rotatingly driving the rotating disk, and a rotating drive means disposed above the rotating disk. A plurality of wafer holders which are dispersedly arranged along the circumferential direction and on which wafers can be placed; a plurality of wafer holder supporting means fixed on a rotating disk to rotatably support each wafer holder; An ion beam irradiating means arranged to irradiate an ion beam from an ion source toward a wafer on a wafer holder. 3. The plurality of wafer holder supporting means supports each wafer holder in parallel with a horizontal plane when the ion beam implantation is stopped, and at an angle inclined with respect to the horizontal plane according to the centrifugal force acting on each wafer holder when the rotating disk rotates. The ion implantation apparatus according to claim 1, wherein each of the wafer holders is supported by: 4. The wafer holder supporting means supports each wafer holder in parallel with a horizontal plane when the ion beam implantation is stopped, and at an angle inclined with respect to the horizontal plane according to the number of rotations of the rotating disk when the rotating disk rotates. A driving mechanism for driving each wafer holder.
Or the ion implanter according to 2. 5. A reciprocating drive means for reciprocating the rotating disk in a radial direction thereof.
5. The ion implantation apparatus according to 2, 3, or 4. 6. The ion beam irradiating means includes scanning means for scanning an ion beam from an ion source in a vertical or horizontal direction on a wafer on a wafer holder. Ion implantation equipment. 7. A plurality of wafer holders are dispersedly arranged along a circumferential direction above a rotating disk disposed in a processing chamber and rotatably supported by a rotating shaft intersecting a horizontal plane, and ion beam implantation is performed. When stopped, each wafer holder on which a wafer is placed is supported rotatably in an upward state, and when the rotating disk is rotated, each wafer holder is supported in an inclined state with respect to a horizontal plane according to the centrifugal force acting on each wafer holder, and tilted. An ion implanter configured to irradiate an ion beam from an ion source to a wafer on a wafer holder obtained by the ion implantation. 8. A plurality of wafer holders are dispersedly arranged along a circumferential direction above a rotary disk rotatably supported by a rotary shaft disposed in a processing chamber and intersecting an inclined surface inclined from a horizontal plane. When the ion beam implantation is stopped, each wafer holder on which a wafer is mounted is rotatably supported in an upward state, and when the rotating disk is rotated, each wafer holder is inclined with respect to a horizontal plane according to the centrifugal force acting on each wafer holder. An ion implanter configured to irradiate an ion beam from an ion source to a wafer on a tilted wafer holder supported by the above.